The number of women with HIV infection has increased rapidly during the past seven years. Despite this, comparatively little is known about the natural history of the disease in women. The rate of decline of immunologic function, the predictors of disease progression, and the efficacies of many therapies have not been determined for women. Several gynecological conditions appear to be influenced by HIV infection. These include fungal vaginitis, infections with human papillomaviruses, and epithelial dysplasias. There is also little information available on conducting clinical research on women, particularly those from demographic groups at the highest risk for HIV infection. We propose to create a regional cohort of 450-600 HIV-infected and 90-120 high-risk, uninfected women as part of the WIHS cooperative multi-site prospective epidemiologic study. The sample size will depend on WIHS goals and funding. The specific aims of our proposed study are: 1) Determine the spectrum and time course of the clinical manifestations of HIV infection; 2) Characterize changes in immunologic function and the relationship between HIV infection, immunologic abnormality and the occurrence of various clinical outcomes; and 3) Investigate factors that are predictive of greater or lesser rates of progression of HIV-related illness, length of survival, and quality of life. In addition, it is our aim to provide data to the WIHS executive committee on the rate of HIV seroconversion among a group of susceptible and high-risk women, factors that may influence the occurrence of seroconversion and the feasibility of conducting vaccine trials in this group. The participants will be recruited from clinical sites and epidemiologic cohorts that have joined together to form the Bay Area Research Consortium on Women and AIDS (BARCWA). This consortium includes university- and community-based investigators and is a joint program of the Departments of Medicine, Oral Medicine and Obstetrics and Gynecology at the University of California, San Francisco. Research activities will be incorporated into primary care services and the project will actively collaborate with community agencies. Based on our extensive experience in cohort studies, procedures will be established to minimize attrition and collect comprehensive clinical data in a consistent manner across several study sites.